How to capture gestures and steps with BMI270 using interrupts?

Question

I am trying to capture steps and wrist wakeup (https://github.com/zephyrproject-rtos/zephyr/blob/4c6b1e5a65e752c881183ddb4687fa0231b11cc3/drivers/sensor/bosch/bmi270/bmi270.h#L112) but I don't see how to do this in the sample document. I thought there would be some way to set the call back for the interrupts like you can do with ble.

I read this post which was very helpful (+) BMI270 interrupts seem not to be usable in nRF Connect SDK v2.2.0 with zephyr - Nordic Q&A - Nordic DevZone - Nordic DevZone (nordicsemi.com), but why aren't the interrupts in the overlay? Shouldn't they be handled there?

I have this working:

const struct device *const accl_dev = DEVICE_DT_GET_ONE(bosch_bmi270);
struct sensor_value acc[3], gyr[3];
struct sensor_value full_scale, sampling_freq, oversampling;

int accelerometer_manager_init(void) 
{
    LOG_DBG("Initializing accelerometer manager");
	if (!device_is_ready(accl_dev)) {
		LOG_ERR("Device %s is not ready\n", accl_dev->name);
		return 0;
	}

    full_scale.val1 = 2;            /* G */
	full_scale.val2 = 0;
	sampling_freq.val1 = 100;       /* Hz. Performance mode */
	sampling_freq.val2 = 0;
	oversampling.val1 = 1;          /* Normal mode */
	oversampling.val2 = 0;

	sensor_attr_set(accl_dev, SENSOR_CHAN_ACCEL_XYZ, SENSOR_ATTR_FULL_SCALE, &full_scale);
	sensor_attr_set(accl_dev, SENSOR_CHAN_ACCEL_XYZ, SENSOR_ATTR_OVERSAMPLING, &oversampling);
	/* Set sampling frequency last as this also sets the appropriate
	 * power mode. If already sampling, change to 0.0Hz before changing
	 * other attributes
	 */
	sensor_attr_set(accl_dev, SENSOR_CHAN_ACCEL_XYZ, SENSOR_ATTR_SAMPLING_FREQUENCY,&sampling_freq);

	/* Setting scale in degrees/s to match the sensor scale */
	full_scale.val1 = 500;          /* dps */
	full_scale.val2 = 0;
	sampling_freq.val1 = 100;       /* Hz. Performance mode */
	sampling_freq.val2 = 0;
	oversampling.val1 = 1;          /* Normal mode */
	oversampling.val2 = 0;

	sensor_attr_set(accl_dev, SENSOR_CHAN_GYRO_XYZ, SENSOR_ATTR_FULL_SCALE, &full_scale);
	sensor_attr_set(accl_dev, SENSOR_CHAN_GYRO_XYZ, SENSOR_ATTR_OVERSAMPLING, &oversampling);
	/* Set sampling frequency last as this also sets the appropriate
	 * power mode. If already sampling, change sampling frequency to
	 * 0.0Hz before changing other attributes
	 */
	sensor_attr_set(accl_dev, SENSOR_CHAN_GYRO_XYZ,SENSOR_ATTR_SAMPLING_FREQUENCY,&sampling_freq);

    return 0;
}

And I can get data by polling this:

void accelerometer_manager_fetch(void) 
{

	sensor_sample_fetch(accl_dev);

	sensor_channel_get(accl_dev, SENSOR_CHAN_ACCEL_XYZ, acc);
	sensor_channel_get(accl_dev, SENSOR_CHAN_GYRO_XYZ, gyr);

    LOG_DBG("AX: %d.%06d; AY: %d.%06d; AZ: %d.%06d; "
		        "GX: %d.%06d; GY: %d.%06d; GZ: %d.%06d;",
	            acc[0].val1, acc[0].val2,
		        acc[1].val1, acc[1].val2,
		        acc[2].val1, acc[2].val2,
		        gyr[0].val1, gyr[0].val2,
		        gyr[1].val1, gyr[1].val2,
		        gyr[2].val1, gyr[2].val2);

}

But getting messages from the senor on a detected activity through a callback was what I was hoping for.

I tried adding this before the return in the first code block:

    struct sensor_trigger trig;
    trig.type = SENSOR_TRIG_DATA_READY;
    trig.chan = SENSOR_CHAN_ACCEL_XYZ;

    if (sensor_trigger_set(accl_dev, &trig, accelerometer_mangager_trigger_handler) < 0) {
        printk("Could not set trigger\n");
        return;
    }

and this above the init:

void accelerometer_mangager_trigger_handler(const struct device *dev, struct sensor_trigger *trigger)
{
    struct sensor_value accel[3];
    sensor_channel_get(dev, SENSOR_CHAN_ACCEL_XYZ, accel);
    printk("Accel X: %d.%06d, Y: %d.%06d, Z: %d.%06d\n",
           accel[0].val1, accel[0].val2,
           accel[1].val1, accel[1].val2,
           accel[2].val1, accel[2].val2);
}

but get this in the console:

Could not set trigger

I have this in my overlay:

    bmi270@68 {
            compatible = "bosch,bmi270";
            irq-gpios = <&gpio1 14 GPIO_ACTIVE_HIGH>, <&gpio1 15 GPIO_ACTIVE_HIGH>;
            reg = <0x68>;
    };

I can fetch the data, but I want to use the interrupt and identify gestures and count steps.

I got it functioning with this in the prj.conf:

CONFIG_BMI270_TRIGGER_GLOBAL_THREAD=y

and this in the code:

    trig.type = SENSOR_TRIG_DATA_READY;    //this works and spits tons of data
	//trig.type = SENSOR_TRIG_DELTA;			//didn't initialize the trigger, caused an eeror on the set command
	//trig.type = SENSOR_TRIG_MOTION;			//passed the set command but not triggering
    trig.chan = SENSOR_CHAN_ACCEL_XYZ;

	int rc;
	rc = sensor_trigger_set(accl_dev, &trig, accelerometer_mangager_trigger_handler);
    if (rc < 0) {
        LOG_ERR("Could not set accelerometer trigger");
        return;
    }

But I still don't understand how to access a trigger or triggers for:

Activity change recognition:

Still
Walking
Running

Wrist gestures:

Push arm down
Pivot up
Wrist shake jiggle
Flick in
Flick out
Wrist wear wake up

BMI270 Context

Step counter and Step detector (Pedometer)
Activity change recognition
Still
Walking
Running

All supported by the sensor:

boschsensortec/BMI270_SensorAPI: This respository contains Bosch Sensortec's BMI270 inertial measurement unit's sensor API. To report issues, go to https://community.bosch-sensortec.com/t5/Bosch-Sensortec-Community/ct-p/bst_community (github.com)

They seem to be supported in Zephyr:
zephyr/drivers/sensor/bosch/bmi270/bmi270_trigger.c at 23eca6362dce63e52fcf6825f772e7ee7ae5226e · zephyrproject-rtos/zephyr (github.com)

Susheel Nuguru · Accepted Answer

We can wait for another community forum member assistance or I think this thread is best suited in the Zephyr forum as this is coming from the Zephyr community as your questions on interrupt support is something we cannot add for this sensor.

How to capture gestures and steps with BMI270 using interrupts?

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